isdn_msg_hdr(D4isdn)
isdn_msg_hdr --
ISDN message header
Synopsis
#include <sys/types.h>
#include <sys/scoisdn.h>
typedef struct isdn_msg_hdr
{
isdnDword_t DL_prim;
isdnWord_t Length;
isdnWord_t AppID;
isdnByte_t Cmd;
isdnByte_t SubCmd;
isdnWord_t MsgNum;
} isdn_msg_hdr_t;
Description
The ISDN message header structure isdn_msg_hdr
is included the control portion of an
ISDN message in Section D7isdn manual pages.
Message parameters (as described in
Section D4isdn manual pages in Section D4isdn manual pages)
are coded in the control portion
following the isdn_msg_hdr.
Structure members
DL_prim
-
The
DLPI
primitive for ISDN is always set to DL_ISDN_MSG.
Length
-
total length of the message, including the complete message
header but excluding the DLPI primitive.
AppID
-
application identifier. The ISDN driver assigns an
application number to an application through the
ISDN_REGISTER
ioctl.
Cmd
-
command, or message type (for example, ALERT,
CONNECT, etc.)
SubCmd
-
subcommand, or message extension (for example, _REQ,
_CONF, _IND or _RESP)
MsgNum
-
message number, included with each message. The ISDN
driver will always return the number used in the
REQUEST message with the corresponding
CONFIRMATION. Applications may choose unique message
numbers to identify message correlations before interpreting
incoming messages. INDICATIONs from the driver will
be numbered so that an application is guaranteed to get
different message numbers for every incoming
INDICATION.
References
Intro(D4isdn),
Intro(D7isdn)
``SCO ISDN adapter drivers'' in Developing MDI network adapter drivers.
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005